typescript - react useState Prop : Type 'string' is not assignable to type 'number' . TS2322

Question

我正在尝试将 Prop 传递给 React useState Hooks。我的 Prop 和数字都是必需的，但我收到 Typescript 错误:

Type 'string' is not assignable to type 'number'. TS2322

但我没有在任何地方传递字符串。所以，我不知道为什么我会得到这个 Typescript。我不想传 Prop any .

import React, { useState } from "react";
import ReactDOM from "react-dom";

interface Props {
  strength: number;
  speed: number;
}

const Courseinfo = ({ strength, speed }: Props) => (
  <>
    <div>
      <h1>{strength}</h1>
      <h1>{speed}</h1>
    </div>
  </>
);

const App = () => {
  const [character, setCharacter] = useState<Props>({ // This Props throws me error 
    strength: 0,
    speed: 0,
  });

  const { strength, speed } = character;
  return (
    <>
      Strength:
      <input
        type="number"
        value={strength}
        onChange={(e: React.ChangeEvent<HTMLInputElement>) =>
          setCharacter({ ...character, strength: e.target.value })
        }
      />
      Speed:
      <input
        type="number"
        value={speed}
        onChange={(e: React.ChangeEvent<HTMLInputElement>) =>
          setCharacter({ ...character, speed: e.target.value })
        }
      />
      <Courseinfo strength={strength} speed={speed} />
    </>
  );
};

ReactDOM.render(<App />, document.getElementById("root"));

Answer 1

input type="number"的值是一个字符串
这是固定的 sandbox .
变化:

interface Props {
  strength: string;
  speed: string;
}

和事件的类型可以是

onChange={(e: React.ChangeEvent<HTMLInputElement>) =>

或者，您也可以转换 event.target.value到一个数字( +event.target.number )而不是改变 Prop 类型。